All Piper PA-34-200 and PA-34-220 series aircraft fitted with a pneumatic pressure operated gyro instrument system.
This Continuing Airworthiness Notice (CAN) advises operators of Piper PA-34-200 and PA-34-220 series aircraft fitted with a gyro pneumatic pressure system of an incident which resulted in a significant fuel leak in the cockpit.
This CAN is prompted by an incident involving a Piper PA-34-200T. Leaking fuel in the engine compartment was drawn into the aircraft’s pneumatic pressure operated gyro instrument system at the air filter inlet which is mounted close to a number of engine fuel lines in the engine compartment. The fuel passed along the air lines into the attitude heading (AH) and direction indicator (DI) instruments, including the pressure gauge. The fuel then leaked from these instruments down the instrument panel onto the front seat occupants.
The pneumatic pump air filter inlet on aircraft manufactured since 1979 is located forward of the aft engine baffle. This configuration was also made available to early PA-34-200T Seneca II aircraft through Piper Service Letter 889 dated 6 November 1979.
This CAN alerts operators of aircraft fitted with a Pneumatic Pressure Operated Gyro Instrument System of the possibility of engine bay contaminants being drawn into the cabin, due to the pneumatic pump air filter inlet being mounted in the engine compartment. The pneumatic pressure system could allow engine bay contaminants such as smoke, carbon monoxide, oil or fuel into the cabin.
Ensure the carbon monoxide indication system in the cabin of the aircraft is serviceable and within any applicable life limit for the system.
